1. Filed of the Invention
The present invention relates to a shutter disposed slidably along a pair of guiderails arranged in an opposed manner in, for instance, an automobile.
2. Related Art
As shown in FIG. 8, in a floor console FC installed in, for example, a compartment of an automobile, an article housing portion 102 that opens upward is defined inside a console main body 100. As a cover member for opening and closing the upper opening 104 of the article housing portion 102, a shutter S1 is employed. In this structure, the slide supporting portions 74 provided at both side edges of the shutter S1 are respectively engaged with a pair of guiderails L1, L2 that are disposed opposedly at the right and left sides of the article housing portion 102, so that the shutter S1 slides in the front-back direction along the guiderails L1 and L2.
The shutter S1 is extended substantially horizontally and flat on the upper surface of the console main body 100 when the article housing portion 102 is closed. When the article housing portion 102 is opened, the shutter S1 is housed in a curved manner in the inside rear portion of the console main body 100. Thus, the shutter S1 is required to be deformed into a flat state and a curved state. In addition, the shutter S1, when the article housing portion 102 is in a closed state, may have an aspect in which, for example, an article or an arm (elbow) is placed on the upper surface thereof, and hands are put on the shutter S1 when passengers get in and out of the compartment. Thus, the shutter S1 is required have flexibility which allows it to be deformed into a curved state and rigidity which supports a certain degree of load thereon. Accordingly, a conventional shutter S1 is comprised of, as shown in FIGS. 9(a) to 10(b), a plate member 60 molded with a soft resin (thermoplastic elastomer, etc.) and a rib member 70 molded with a resin (polyethylene, polypropylene, acrylonitrile butadiene styrene (ABS), polycarbonate, etc.) harder than the soft resin. In other words, the conventional shutters S1 are produced by means of what is called multicolor molding method, and those which are molded from two or more types of resins having different hardness are employed.
In the above-described plate member 60, cell portions 62 and hinge portions 64 thinner than the cell portions 62 are formed alternately in the sliding direction, so that elastic curvature deformation can be made at each hinge portion 64. Further, each rib member 70 comprises a rib portion 72 extended along the cell portion 62 and slide supporting portions 74 provided respectively at one end and the other end of the rib portions 72. The respective rib members 70 are separated from each other individually in the sliding direction, in which the rib portion 72 is mated with the cell portion 62 of the plate member 60, and each slide supporting portion 74 is elongated sideward beyond the plate member 60. Accordingly, the shutter S1 is able to slide along the guiderails L1 and L2 when the respective slide supporting portions 74 of each rib member 70 engages with the groove portions 114 of the corresponding guiderails L1 and L2. The shutter S1 designed in such a manner as describe above is disclosed in, for example, Japanese Patent Application Laid-Open (Kokai) No. 2008-24099
Each rib member 70 in the above-described structure is in such a form that its two slide supporting portions 74 are engaged with the groove portions 114 of the guiderails L1 and L2. Accordingly, when a load is applied thereto from the front side of the shutter S1, it is supported by the guiderails L1 and L2 in a two-point support fashion in which the line B1 that connects the abutting points P1 and P2 of both slide supporting portions 74 becomes one straight line as shown in FIG. 11(a). Moreover, the abutting portions 74A of the slide supporting portions 74 are in a form of spherical body so as to decrease the frictional resistance with respect to the groove portions 114 of the guiderails L1 and L2. Accordingly, when a load is applied to the rib portion 72 of the slide supporting portion 74 at a position shifted from the line B1 in the sliding direction, the rib member 70 ends in rotational displacement around an axis extended in the width direction of the shutter. Accordingly, as shown in FIG. 11(b), when a load is applied to the hinge portion 64 of the plate member 60, the rib members 70 adjoining the hinge portion 64 come to be rotationally displaced reversely around an axis extended in the width direction. As a result, there is a fear that the plate member 60 is broken at the hinge portion 64 due to the concentration of stress on the hinge portion 64. Furthermore, when a load is applied from the front side of the shutter S1 in a state that the rib portion 72 declines, the rib member 70 fails to show pre-designed rigidity, and there is a possible fear that the rib member 70 is broken.